一.场景准备
测试场景为MySQL 8.0：主键重复场景唯一键重复场景1、空洞建表，主增值包含主键及唯一约束
复制CREATE TABLE t1(
id int(11) NOT NULL auto_increment,键自
c1 varchar(64) DEFAULT NULL,
c2 int(11) DEFAULT NULL,
PRIMARY KEY (id),
UNIQUE KEY uk_c1 (c1)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;1.2.3.4.5.6.7. 2、写入初始测试数据复制insert into t1 (c1,空洞c2) values (a,1),(b,2),(c,3);
mysql> select * from t1;
+----+------+------+
| id | c1 | c2 |
+----+------+------+
| 1 | a | 1 |
| 2 | b | 2 |
| 3 | c | 3 |
+----+------+------+
3 rows in set (0.00 sec)1.2.3.4.5.6.7.8.9.10.11.二.开始测试
insert into复制# 测试主键重复
mysql> insert into t1 values (1,aaa, 111);
ERROR 1062 (23000): Duplicate entry 1 for key t1.PRIMARY
# 测试唯一键重复
mysql> insert into t1 (c1,c2) values(a, 4);
ERROR 1062 (23000): Duplicate entry a for key t1.uk_c11.2.3.4.5.6.7. insert ignore intoinsert方式插入数据在处理过程中发生主键传统等错误时候，语句会被终止，主增值并告知错误的亿华云计算键自原因。而使用insert ignore的空洞方式进行数据插入，则会忽略插入错误的主增值行继续插入没有问题的b2b信息网行记录，最终以warning进行提示。键自
复制# 测试主键重复
mysql> insert ignore into t1 values (1,空洞aaa, 111);
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql> show warnings;
+---------+------+------------------------------------------+
| Level | Code | Message |
+---------+------+------------------------------------------+
| Warning | 1062 | Duplicate entry 1 for key t1.PRIMARY |
+---------+------+------------------------------------------+
1 row in set (0.01 sec)
# 测试唯一键重复
mysql> insert ignore into t1 (c1,c2) values(a, 4);
Query OK, 0 rows affected, 1 warning (0.00 sec)
mysql> show warnings;
+---------+------+----------------------------------------+
| Level | Code | Message |
+---------+------+----------------------------------------+
| Warning | 1062 | Duplicate entry a for key t1.uk_c1 |
+---------+------+----------------------------------------+
1 row in set (0.00 sec)1.2.3.4.5.6.7.8.9.10.11.12.13.14.15.16.17.18.19.20.21.22.23.在测试过程中惊奇地发现测试表中的主键自增列发生了改变，经过之前的WordPress模板主增值操作已经变成了7：
复制mysql> show create table t1\G